The invention relates generally to motor vehicle grilles positioned at the front ends of vehicles, and in particular to grilles attached to the hoods of motor vehicles.
Automobile and truck grilles originally served as a protective barrier and as a source of ventilation for the radiator. Today, grilles continue to provide a ventilation function, but also normally serve as decorative features and are often incorporated into the vehicle bumper for aerodynamic and styling purposes. On some vehicles, design esthetics or engineering considerations have resulted in the grilles being attached only at their upper edge to the vehicle's hood. For instance, government regulations mandate automobile bumpers that can absorb low-speed impacts without damage. Bumpers that contract up to 3 or 4 inches on frontal impact and then automatically rebound from the impact accomplish this. The possibility of bumper contraction has necessitated a redesign of automobile grilles. Various solutions to this grille design problem have arisen, including grilles that are attached to the hood in some fashion so they can swing back out of the way on impact or grilles that can resiliently deflect with the stroke of the bumper.
Such hood-mounted grilles are minimally attached to the hood at their upper end so as to be capable of movement during impact. Depending on the amount of bracing included in the attachment, such grilles may become susceptible to aerodynamic and road-induced vibrations and flutter when the hood is in its closed position. This problem is generally solved by costly additional reinforcements attached to the grille itself. For example, in U.S. Pat. No. 5,478,127, the grille has a dual support arrangement in which an upper edge is resiliently attached directly to the automobile engine hood and the lower edge is resiliently supported by additional support members that connect the grille's lower edge to the engine hood. This solution obviously entails added weight, complexity, and manufacturing costs.
Accordingly, what is needed is a simple and economical means to prevent vibrations in a vehicle having a hood-attached grille.